Japan’s Power Meter Deployment
with ECHONET Lite over IPv6

Masaki Umejima

Fellow, Echonet Consortium
Deputy chairman, Smart House
and Building Committee, JSCA
Deputy Director of the Auto-ID Laboratory
Keio University Research Institute at SFC

1. Discussions in JSCA regarding thedeployment of an open standard interface
The Information Economy Committee of the Ministry ofEconomy, Trade and Industry’s Industrial Structure Council
held architecture-level discussions on the system theory aspects ofHome Energy Management Systems (HEMS) and on the overall
strategy regarding smart houses.
An energy management system is a system that implements
Demand Side Management (DSM) to improve the efficiency
with which energy is used at the customer side. There was a
discussion on the subject of whether the system architecture
should be vertically integrated with a closed interface, or should be
horizontally specialized with an open interface.
A review of the published proceedings will show that a lively
debate took place, but through these architecture-level discussions,
it was resolved that new participants should be encouraged torealize innovation in relation to smart houses, emphasis shouldbe placed on increasing the potential for added-value creation not
limited solely to energy management, and the design of smart
houses by horizontally specialized architecture based on known
standard interfaces should be promoted.
With a horizontally specialized architecture, the overall system
is built by using predetermined interfaces to assemble together
smaller systems (subsystems). This results in a configuration withredundancy in the connections between subsystems (Carliss Y.
Baldwin, Kim B. Clark, 2000).
Conversely, in a closed system that can be easily customized,
it is easy to obtain a streamlined design that has little redundancy.
Nevertheless, open systems that are wasteful in various aspects areused because of the larger incentives for the construction of many
diverse systems at the same time.
In an open system, the interface selection is done in advance.
Pre-selection of the interface is therefore essential. Anotherimportant is implementation. In gathering key players on demandside management such as Toshiba, Panasonic, NTT, Japanese
Government has launched Smart House and Building Committee
in JSCA.

2. Decision to recommend ECHONET Litebased on a public-private partnership
ECHONET is a home network communication protocol
created by the ECHONET Consortium, which was founded in
1997 by a group mainly comprised of Japanese manufacturers ofconsumer electrical products with the aim of standardizing theimplementation of home automation.
The distinguishing feature of this protocol is that it facilitatesdetailed control of Japanese consumer electrical products. On the12New Breeze Spring 2015

other hand, since it defines interfaces for everything from physicalmedia to application software, it is unable to adapt to the global
trend towards the increasing use of IP at the network layer.
In particular, the presence of ECHONET addresses, which
are intended to facilitate seamless connections to various physicallayers, presents a major barrier to the formation of an international
strategy. In response to requests from the public and private
sectors, the ECHONET Consortium investigated the ideaof abolishing ECHONET addresses and switching to a newcommunication protocol consisting of the ECHONET protocol
superimposed on a physical layer using ordinary IP addresses.
This culminated in ECHONET Lite, which was released bythe ECHONET Consortium on in July 2011. This specification
has a new interface definition that does not define the physicallayer and only defines parts of applications and the commandsystems of domestic electrical appliances and facilities.
■Table 1: The leading smart house interfaces used inJapan and overseas
Type

Name ofspecification

SummaryJapanECHONET LiteIP-based. Compatible with XML, etc.
Defined for over 80 different devices. Allows
detailed control

U.S.

SEP

IP-based. Predominantly offers superficial
access to crude controls

EuropeKNX

Considerable experience ofimplementations in places on a larger scalethan residential buildings (e.g., BEMS)

The two changes made by the ECHONET Consortium tothe technical specifications (synchronizing with IP and leaving
the physical layer unspecified) have had a major impact. This isbecause it facilitated cooperation with other protocols that havealready been deployed and achieved international standardization.
It could also be said that these changes made the protocol easierfor new businesses and overseas businesses to use.
Although ECHONET Lite is sometimes criticized for beinga Japan-only specification, this is not actually true. There are still
many things that could be improved — for example, there are notraining systems in place (even for engineers), no SDK or softwaredevelopment environment has been set up, and the only countries
with equipment certification systems in place are Japan andMalaysia. However, it would be incorrect to call ECHONET Litea national standard.
First, it has been ratified as an IEC standard. Second, theECHONET Lite specification is an open standard. Third, it
synchronizes with the direction of architectural maintenanceof the international M2M network maintenance. And fourthly,
it is being used in a growing number of implementations. The

simultaneous promotion of these four factors is bringing ■ Figure 1: The ECHONET Lite protocol stack
ECHONET Lite to a firm international standing.
The ECHONET Consortium has received the supportof the JSCA Smart House/Building Standardization andBusiness Promotion Study Group (established as a public/
private partnership in Japan), and selected the IEC as thestage for the acquisition of international standardization,and has been steadily promoting de jure internationalstandardization.
Specifically, it is participating in ISO/IEC JTC1 SC25
WG21, IEC TC57 WG21 and IEC TC100 in order toascertain the trends in international standardization andengage in consultations with experts from around the world.
Its main activities are outlined below. First, with regard to
the standardization of ECHONET Lite, progress is being
made in establishing the ECHONET Lite specification(ISO/IEC14543-4-3) as a communication standard in theform of a supplement to the ECHONET specification
I also hear from overseas manufacturers that they are studying(ISO/IEC14543-4-1,2) that has already become an international
the writing of their own country’s specifications for consumer
standard. Second, an expanded proposal is also being preparedelectrical equipment and sensor devices. By paying a registration
whereby control target objects (also usable in ECHONET Lite)
fee of just ¥300,000 (less than $3000 in U.S. dollars), anyone inare added to the ECHONET specification (IEC62394).
the world can help write the specifications for new ECHONET
The ECHONET Lite specification (which is the unique
Lite equipment.
intellectual property of the ECHONET Consortium) also playsa large role in open standard decision-making. All the technical
3. Leading implementation of “B Route” smart
specifications can currently be obtained via the ECHONETmeters
Consortium’s public web site (http://www.echonet.gr.jp/spec/
In March 2012, the Ministry of Economy, Trade and Industryindex.htm).
Smart Meter System Investigation Committee announced that
With regard to this decision-making, the ECHONET
users of electric power usage information would be introducing
Consortium’s Representative Director Morio Hirahara has statedthe “B-route” technical specifications acquired directly fromthe following:smart meters. This smart meter specification, which required the“ECHONET Lite will only become valuable when everyone isimplementation of an IPv6 single stack and ECHONET Lite, has
using it and a market has grown around it. There is no point inachieved global recognition as an advanced architecture.
guarding it jealously. In manufacturing, a leading manufacturer
The author gained the opportunity to lead the development
can make anything from scratch, but in networks, one shouldof this specification, but in fact before the announcement of thisremember that value is expressed by connecting diverse equipment
specification, the smart meters had become a symbol of Japan’s
together. I hope that we can create products with the participation
closed architecture, but since this announcement there has been aof people from as many different business fields as possible.”
lot less criticism of this sort, especially from overseas.
In practice, since the “four decision-making”, the members
At present, the implementation of smart meters usingof the ECHONET Consortium rapidly increased from 20
B-route is progressing smoothly. This stepped up a gear with thecompanies to over 200, stimulating the activity of participation inopportunities presented by the July 2014 publication of smart
the ECHONET Consortium. (Figure 1)
meter specifications for the Tokyo area (TEPCO) and Nagoya
The number of devices compatible with ECHONET Litearea (Chubu Electric Power). The US media company Bloomberg
is continuing to grow steadily. At present, devices for which thehas reported that by 2020, 85% of Japan’s demand for electricity
specifications have been fixed account for not just consumer
will be obtained through smart meters. New smart meters areelectrical products but over 90 different types of equipment.
being installed in every home in Japan ahead of the rest of theConventionally, the properties of air conditioners, lighting andworld, and it is expected that Japan will lead the world in theother devices that use energy are defined, but the properties ofinnovation of smart meters and the IOT (Internet of Things).
photovoltaic solar cells, fuel cells and storage batteries are defined.
REFERENCES
In addition to consumer electrical products that use electricity, it is1) Baldwin, C.Y., and Clark, K.B. [2000], Design Rules: The Power of Modularity, Cambridge,
MA: MIT Press. (Translation by Haruhiko Ando [2004], Design Rules, Toyo Keizei)
also intended that the same ECHONET Lite protocol should be2) Chesbrough, H.W. [2003], Open Innovation, Boston, MA: Harvard Business School Press.
used to connect devices that create or store electricity in the home.
(Translation by Keiichiro Omae [2004], “Open Innovation” SANNO Institute of Management
Publication Dept.)
By using ECHONET Lite, a well-known standard interface,3) Ulrich, K.T. [1995],“The Role of Product Architecture in the Manufacturing Firm,” Research
to connect diverse types of domestic appliances to a network, wePolicy 24 419-440.
4) Masao Isshiki, Masaki Umejima, Morio Hirahara: The Significance of Smart House Interfacearrived at the implementation of an environment in which theyStandardization, OHM, October 2012, 22–27
can be integrally operated as a Home Energy Management System5) Ministry of Economy, Trade and Industry: Proceedings of Industrial Structure Council andInformation Economy Committee, 15th June 2011
(HEMS).

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